| CPC C10M 143/12 (2013.01) [C10M 2203/003 (2013.01); C10M 2205/06 (2013.01); C10M 2219/044 (2013.01); C10N 2020/02 (2013.01); C10N 2030/02 (2013.01); C10N 2030/04 (2013.01); C10N 2030/10 (2013.01); C10N 2040/04 (2013.01); C10N 2040/25 (2013.01)] | 24 Claims |

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1. A lubricating oil composition comprising or resulting from the admixing of:
(i) at least 50 mass % of one or more base oils, based upon the weight of the lubricating oil composition;
(ii) one or more dispersants;
(iii) one or more detergents; and
(iv) one or more styrenic block copolymers having:
a) a radial structure where one or more blocks derived from conjugated diene monomers are distal to the radial center and one more blocks derived from vinyl aromatic monomers that are proximal to the radial center;
b) line roughness, Ra, of 7 μm or more, as determined by Keyence surface analysis of the neat polymer; and
c) an intrinsic viscosity, [η], measured at a shear rate of 2×106 s−1 at 40° C. that is less than the intrinsic viscosity measured at a shear rate of 2×106 s−1 at 80° C., as determined by Ultra Shear Viscometry analysis on a blend of 99.8 mass % of Group III base stock having a viscosity index of greater than 120 and a KV100 of about 4.0 cSt and 0.2 mass % copolymer.
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